Mechanism and process for fabricating flexible shafting



Aug. 4, 1931.

R. c. VANGELL Re. 18,142

MECHANISM AND PROCESS FQR FABRICATING FLEXIBLE SHAFTING 4 Sheets-Sheet 1Original Filed Aug. 7, 1924 N NDE m 5N mm a N N H w. M g Q v Q @N N n RR E Q HN NN R Na wan QN w". NQ' 0. mm a I Q hm .w Sm a Q 9w 2r w R w m 1\cN/g m r w 1.1 a; 5/ 19/ v r/vw NN QQ a n ha SHE MN h H w mm Q NW mw RmEm @m m an N? E Aug. 4, 1931. R, ANGELL Re. 1s,142

MECHANISM AND PROCESS FOR FABRICATING FLEXIBLE SHAFTING Original FiledAug. 7, 1924 4 Sheets-Sheet 2 I N VEN TOR.- Robert C. 29653,

A TTORNEYS.

Aug. 4, 1931. R. c. ANGELL ME-CHANISI AND PROCESS FOR FABRICATINGFLEXIBLE SHAFTING 4 Sheets-Sheet 3 Original Filed Aug. 7, 1924 INVENTOR-Aug. 4, 1931.

R. C. ANGELL MECHANISM AND PROCESS FOR FABRICATING FLEXIBLE SHAFTINGOriginal Filed Aug. 7, 1924 4 Sheets-Sheet 4 INVENTOR:

ATT

Reiuued Aug. 4, 1931 1 UNITED STATES PATENT oar-10E ROBERT Cl AN GELL,OF PRINCE BAY, NEW YORK, ASSIGNOB TO THE S. 8. WHITE DENTALIANUFACTURING COMPANY A CORPORATION OF PENNSYLVANIA KECEANISM ANDPROCESS FOR FABRICATING FLEXIBLE SEAFTING Original'll'o. 1,671,951,dated Kay 29, 1928, Serial No. 780,740, fled August 7, 1924. Applicationfor I reissue filed February 5, 1980. Serial No. 428,171.

My invention relates particularly to that class of mechanism wherein alayer of wire is helically coiled around a core to form a flexibledriving shaft for connecting movable elements for synchronous actuation.

In the production of flexible shafting formed of a lurality of layers ofwire or strip material superposed in coiled relation one upon the other,there are considerable stresses and strains, due to the tension whichmust be exerted in the bending of the individual elements in coilingthem about the core, which tends to producetorsional stress and aninitial pressure contact between the u helically wound elements and thecore and which effects undueinternal friction when such shaft is rotatedabout its axis in flexed or curved condition, and furthermore, there isa tendency of this product when released to twist upon itself into atangled mass. Owing to the inherent stresses and strains produced by thetension of the individual elements of such shaft it has heretofore beenimpractical to produce shafting which is suffl ficlently free frominternal friction to be successfull employed as a driving shaft, exceptin llmited lengths.

The principal object of my invention is to provide in flexible shaftproducing mecha- 30 nism, means tending to so untwist or recoil theshafting as to relieve the initial stresses incident to the tensionexerted in the laying on of the elements of the superposed windinwhereby an inert flexible shaft, and one su stantially free frominternal friction and embodyin the desired flexibility, may be produced1n what may be termed continuous ength, or shaft that may be taken up byspooling mechanism as fabricated.- Any length of shaftin may beconsidered continuous when it 0 such length that the end efl'ects, asthey are termed, ma be ignored,

i.e. is so long that the efiect 0 any stresses.

and strains at the free ends of this length do not alter or modify thecharacteristics of my continuous fabrication procedure or of the productresulting from this procedure.

When I speak of recoiling the shafting I refer to a partial untwist-ingor uncoiling ll of the outer, or last applied, helical laye'r 'view ofsaid machine taken on the line during the fabrication of the shafting.This artial untwisting or uncoiling of the said ayer will alsosimultaneously slightly twist the core or underl ing body upon whichthis layer has been laid to form a composite shaft; and my inventioncontemplates and takes account of this simultaneous twisting of theouter layer and the underbody. But the important object of this twistingoperation is to effect the slight recoil or turning back of the lasthelically wound coil whereby the over-tight winding of that coil isrelieved, with a correspondlng relief of the in ternal stresses andstrains occasioned b the too great pressure contact, which theabrication of the shafting has occasioned, between the helical layer andthe underlying body. In this way the fabricated shaft is not onlyrendered inert, but is also substantially free from internal frictionwhen employed as a turning or connecting shaft and is rotated orotherwise actuated in a flexed or curved condition.

Specifically stated one form of my invention, as hereinafter described,comprises a core spool carrier or payout mechanism, a wire bobbincarrier or winding mechanism, and recoil or untwisting mechanism, and atake-up reel or spooling mechanism, upon which the fabricated shaftingis wound, and means whereby the rotation of the independent units aboutthe axis of the shaft may be relatively varied.

My invention also includes all the various novel features ofconstruction and arrangement as hereinafter more definitely s cified.

In. the accompanying drawings, ig. I is a vertical longitudinalsectional view of a machine constructed in accordance with my invention.

Fig. II is a transverse vertical sectional view of the machine shown inFig. I taken on the line IIII in said figure.

Fig. III is a transverse vertical sectional IIIIII in Fig. I.

Fig. IV is a transverse vertical sectional view of said machine taken onthe line IV-IV in Fig.1.

Fig. V is a side elevational viewof a short m length of the fabricatedstructure forming the shaft and showing the first layer of strandscoiled upon the core.

Fig. VI is a. slde elevational view of a section of said shaft showingthe second layer of strands coiled thereon.

Fig. VII is a side elevational view of a section of said shaft showingthe third layer of strands coiled thereon.

Fig. VIII is a vertical longitudinal sectional view of a machineembodying a slight modification of construction.

Fig. IX is a vertical longitudinal sectional view of a machine embodyinganother modification of construction; and

Fig. X is a transverse vertical sectional view taken through the take-upreel on the line X-X in Fig. IX. Y

The machine shown in Figs. I to IV inclusive may preferably be composedof separate units cooperatively connected and comprising a core payoutcarrier 1, the wire dispensingand winding or laying-on mechanism 2, therecoil or untwisting mechanism 3, arranged to rotate the shaft about itslongitudinal axis, and the take-up or spooling mech- I v anism 4.

guided through the hollow trunnion 7.

Rotation of the flier-frame 5 upon the axis of the core may be effectedin any convenient manner, but I have chosen to illustrate a simplemethod which comprises the pulley 13 secured on the trunnion 6, andhaving va in diameters arranged to be connected by il ie belt 15 with asimilar stepped pulley 16 on the countershaft 17.

The wire-feeding and winding mechanism comprises the bobbin frame havingits end walls comprisin the disks 20 and 21 connected by the spacing ars22, and respectively having hollow trunnions 23 and 24 mounted forrotation in the standards 25 and 26, the trunnion 23 being extendedinwardly to form the hollow stud 27 upon which the bobbins 30, 31, 32and 33 may be rotatably mounted and removably held in position thereonby the disk 35, which is retained on the stud 27 by the retaining nut36.

Said bobbins 30, 31, 32 and 33 are respectively arranged to deliverwires 37, 38, 39 and 40 to the die 42, suitably mounted in the disk 21and having therein suitable apertures 43 through which said wires arearranged to pass, and the aperture 44 for the core 12, which is directedthrough the hollow trunnion 23, hollow stud 27 and hollow trunnion 24,and about which said wires 37, 38, 39, and

40 are coiled by the rotation of the wire bobbin frame and its die 42.The wires 37, 38, 39 and 40 are respectively directed to the die 42 bypassing over suitable guide rollers or pulleys 45, preferably carried bythe spacing.

bars 22, and over the guide rollers or pulle s 46, which may beconveniently carried by t e.

thus formed may be progressed longitudinally, at a predetermined rate ofspeed, by the recoil mechanism comprising the drum 52, around which saidstructure may be wrapped for one or more turns, and which is mounted forrotation in the frame 53 on an axis transverse to the direction oflineal movement of the shafting and having its peripheral surface intangential relation with respect to the lineal axis of said shafting;thereby producing both an axial draft and a transverse or radialpressure on the external coils of the axially moving shaft which willcontrol its movement: i. e., will hold it against slipping or rotativemovement on, or relative to, the drum surface. Mechanism whichaccomplishes this latter function may be termed controlling or holdingmechanism.

Said frame 53 is itself mounted for independent rotation about the axisof the shafting, having trunnions 55 and 56 mounted for rotation in thestandards 57 and 58, and being provided with an aperture 59 forming a.guide through said trunnions 55 and 56 for the passage of the shafting,which as already stated, is arranged to be wrapped one or more turnsaround the surface of said drum, from which it passes to the take-upmechanism, to be hereinafter described.

The trunnion 55 of the recoil mechanism is provided with the steppedpulley 60, which is connected by the driving belt 61 with the steppedpulley 62 on the counter-shaft 17, and may be rotated with the corepay-out mechanism at different speeds in the same or opposite directionas maybe determined b the desired direction of rotation of the win ingmechanism in the application of the succes'sivehelically coiled layersof wire; it being obvious that this direction of rotation of the saidwindingmechanism must be reversed in, the steps of first applying aright hand helical winding such as is shown in Fig. V and then a lefthand helical winding such as is shown in Fig. VI. But it will also beobvious, from the disclosure of the drawings and of-the precedingportion of this s cification that the direction of rotation of t erecoil mechanism I recoil per unit of length of the fabricated product.The steps of the pulley 62 enable me to employ a different amount ofrecoil in each successlvely applied layer of the helically disposedwindings.

Positive rotation of the drum 52 on its axis may be effected throu h theWorm gear 63 on the shaft 64 of said rum, by cooperation with the worm65 whose shaft 66 carries the gear 67 in mesh with the gear 72 which issecured in stationary relation upon the standard 57. This positiverotation of the drum 52 on the shaft 64 results in a fixed and constantaxial movement of the shaft, which re sults, in turn, in a fixed andpredetermined pitch of the successive coils of the helically wound layerof wires as they are applied to the core by the action of the windingmechanism.

The take-up mechanism comprises the take up reel 75 having its shaft 76mounted for rotation in the standards 77, and provided with the pulley78 connected by the belt 7 9 with the pulley 80 on the countershaft 17.The puley 80 drives the take-up reel at a rate suflicien .1- to advancethe shaft at a constant speed of delivery as it passes from the drum 52to the take-up reel ;any difference of rotative speed required for thetake-up reel being provided for b slippage of the cord 79 on the pulley80. t is obvious that the maintenance of this tension in the product asit is wound on the take-up reel 75 will prevent the product so woundfrom any rotative movement thereafter about its own axis. It followsthat the extent of the rotation of the recoil head or mechanism on thetrunnions 55, 56 determines the extent to which the shaft is recoiledduring its passage from said recoil mechanism to the winding drum. Ihave used the term recoil to denominate the twisting of the shaft duringfabrication in a direction opposite to that in which the last helicallayer has been wound about the core, accompanied by a relieving of thatinternal pressure which was effected b the unavoidably too tight windingof the elical coils on the core by the action of the winding mechanism.

The various stages of construction of the fabricated shafting aredepicted by enlarged illustrations in Figs. V, VI and VII; the firstlayer of wires 37, 38, 39 and 40, being laid side by side in coiledrelation about the core 12, as shown in Fig. V; the second layer ofwires being laid upon the first layer in opositel directed coiledrelation, as shown in ig. and the third layer of wires being coiled incrossed relation to the second layer, as shown in Fig. VII, whereby thecomposite shaft is formed by successive layers of four wires eachdisposed side by side, it being understood however, that the machine maybe adapted to form the shaft by fabricating the layers of one or morewires, and said shaft may be formed of as many layers as may be deemedpractical.

In the form'of m invention shown in Fig. VIII, the longitu 'nalprogression of the shaft'may be effected solely by the take-upmechanism, which may be so driven as to produce a predetermined constantaxial movement of said shaft. Said take-up mechanism comprises thetake-up reel 105, having its shaft 106 mounted for rotation in thestandards 107, and provided with the pulley 108 connected by the belt109 with the pulley 110 which is carried by a suitable slide frame 111mounted for longitudinal movement on the countershaft 100, and having afriction wheel 112 arranged to engage either of the opposed surfaces ofthe friction disks 113 and 114.

The friction wheel 112 is arranged to be held in engagement with thefriction disks 113 and 114 by the double bell-crank-lever 115, which hasone arm engaged with the slide-frame 111 which has its laterallyextended arms 116 and 117 provided with suitable hooks 118 and 119'arranged toreceive the loop or ring 120 of the weight 121. As will beobvious, said weight may be engaged with eiiher of said hooks 118 or119, depending upon which of the friction disks 113 and 114 the frictionwheel 112 is to be engaged, and upon the direction in which thecountershaft 100 may be rotated.

In this form of my invention shown in Fig. VIII, the recoil drum 125,which is mounted for rotation inthe frame 126 is rotated on its own axisby the take-u mechanism pulling on the fabricated sha t, which iswrapped around said drum 125, as shown, and requires no gearing such asshown in Fi I. The recoil drum frame 126 is rotate as a whole about theaxis of the product being formed by a ste ped pulley drive such as hasbeen previous y described and, in Fig. VIII, I have chosen to show thecore dispensing bobbin and the recoil frame so connected with thedriving shaft as to rotate at relatively difi'er ent speeds.

In the form of my invention shown in Figs. IX and X, the holding drum130 is mounted for rotation about the axis of its shaft 131 which iscarried b bearin s in the standard 132, said rotation eing e ected bythe axial movement of the product, which 1s wrapped one or more timesaround said drum and drawn forward b the take-up reel 135.

In this form 0 my invention, the take-up reel 135 not only rotates onits own axis to longitudinally progress the flexible shaft, but it isalso arranged to rotate bodily around the longitudinal axis of saidshaft, the said reel 135 being supported in the frame 137, which has thetrunnions 138 and 139 mounted to rotate in the standards 140 and 141,these trunnions being provided with the bore 142 through which the shaftpasses to said reel 135. The rotation of said frame 137 may be effectedby the stepped pulley 143 which is connected by the belt 144 with thestepped pulley 145 on the countershaft 146. In this form of myinvention, as in the two pre viously described forms, I employ thestepped pulleys 143 and 145 for the purpose of obtaining variouspredetermined amounts of recoil per foot of length of the last appliedlayer; and thus I may progressively vary the amounts of the said recoilin the successively applied helically disposed windings.

The shaft 136 of the take-up reel 135, is arranged to be rotated by atrain of gearing comprising the worm gear 147,worm 148, on the wormshaft 149 having the pinion 150 in toothed engagement with the gear 151,which is secured on the standard 140, so, as will be obvious, when theframe 137 is rotated about the longitudinal axis of the shafting, thetake-u reel 135 will be caused to rotate on the axis of its shaft 136.

It will also be obvious that the take-u reel 135 and the worm gear 147may both secured to the shaft 136 so as to rotate the reel at apredetermined speed and consequently draw out the fabricated shaft at alike speed, but if the roll is to be used to spool or wind up a numberof superimposed layers of fabricated product, said worm gear 147 isloosely mounted to rotate on the shaft 136 and is frictionally connectedwith the take-upreel 135 by any desired form of tension mechanism, such.for typical illustration, as shown in Fig. X, wherein the frictiondisk152 is forced into engagement with the worm gear 147 by the spring 153and the tension varied by the adjusting nut 154, whereby any desiredpull may be exerted to draw out said fabricated shaft.

Although, in this form of my invention, the holding drum 130 does notrotate bodily about the longitudinal axis of the fabricated shaft. as inthe other forms of my invention, it will be obvious, that said drumcooperates with the take-up mechanism whose take-up reel 135 is-arrangedto rotate bodily about the longitudinal axis of the shaft being fabrilcated, to efiect the same recoil or untwisting of the last wound helicallayer of said shaft, as is accomplished by the equivalent rotation ofthe drum frames 53 and 126 of the previously described embodiments of myinvention.

It is to be understood that the means herein shown and described foractuating the associated parts of my improved apparatus is typical andsimply for illustrative purposes, as it is obvious that the parts may bereadily connected for cooperation by other means,

such, for instance, by suitably correlated gearing.

Furthermore, it is to be understood that the core body herein referredto may consist of a single mm or may be composed of a plurality of wireslaid parallel, or coiled about each other in any form desired, as forexample as shown in Figs. V and VI.

My invention is advantageous in that the composite product thus formedmay be so rotated upon its longitudinal axis as to relieve the initialtorsional stress imposed on the shaft elements during fabrication, sothat when spooled upon the take-up, reel the fabricated shaft will besubstantially free from a tendency to twist upon itself and tangle, andwhen employed as flexible driving shaft it will be substantially freefrom internal friction when rotatedin flexed or curved condition. It isobvious that these results will be accomplished by the partial uncoilingor recoiling of each belically wound layer of wires after they are laidon the core body; because when the parts are proerly adjusted andoperated, as before described, at uniform predetermined speeds, thepitch of each helical winding, and the length of the wire therein,remains constant for each unit length of the product as it is progressedthrough and drawn from the winding mechanism; and when this product isafterwards rotated on its longitudinal axis, as described, this actionnecessarily alters this pitch by reducing the number of helical coilsper unit of length of the fabricated. shaft; and this. in turn,permanently enlarges the inner diameter of the helical winding withoutsubstantially altering its axial length with respect to its core,thereby relieving the initial pressure stress or contact engagementbetween them and the underlying body on which they were wound.

When the underlying body consists of a core and one or more overlyinghelical layers, as shown for exam le in Fi V or VI- then the effect oftwisting the fa ricatcd shaft in the manner described is not only toincrease the inner diameter of the last applied helical layer but alsoto decrease, the outer diameter of the core body, and thus relieve theressure contact therebetween by the relative change in the diameters ofthese two parts. In the twisting of the underlying layerwhich tends todecrease its external diameter--the underlying layer or layers arereturned to a certain degree to the condition in which they were beforethey were individually subjected to previous recoil actions; but, theyare not completely returned to such condition because, I ordinaril giveto the last applied layer a lesser recoi effect than has been given toany of the previously wound layers.

In all cases each of the recoil operations, or the aggregate of all ofthe recoil operationsif the shaft comprises more than one helicallayerresults in a permanent increase in the diameter of each of the saidlayers relative to the diameter of the underlyin body and this producesa fabricated pro not having the desired freedom from internal frictionwhen used as a torque-transmitting element; and this structuralcharacteristic is one which is present in the fabricated productindependently of any effect which may result from subsequent torsionalstress incident to the subsequent use of the shafting.

I do not desire to limit my invention to the precise details ofconstruction and arrangement as herein set forth, as it is obvious thatvarious modifications may be made therein without departing from theessential features of my invention as defined in the appended claims.

Having thus described my invention, I claim:

1. In a machine for the fabrication of flexible shafting in continuouslengths the combination of mechanism arranged to feed a core, mechanismfor applying thereto a helically wound layer of wire, holding mechanismwhich engages the surface of the said helical layer and prevents itsrotation with respect thereto without interfering with its progressiontherethrough, a take-up mechanism, and mechanism which efiects rotationof one of the last two mentioned elements around the axis of theshafting at any predetermined speed and thereby produces a controllableuntwisting of the said helical layer and a concurrent permanent twistingof the 'said core to relieve the initial pressure engagementthe'rebet'ween.

2. In a machine for the production of flexible shafting in continuouslengths, the combination of mechanism for applying a helically woundlayer of wire to a moving core, mechanism for spooling said shafting,and mechanism inter osed between said winding mechanism an said spoolingmechanism and co-operating therewith to effect a predetermined rotationof the said helical layer in a direction opposite to that in which it iswound and maintain it in this recoiled position throughout the spoolingoperation, to thereby obtain a permanent .relief of the initial pressureengagement between the said layer and the said core.

3. In a machine for the production ofcontinuous lengths of flexibleshafting the combination of mechanism for progresslng a core, a windinghead for superimposing a helical layer upon said core, and mechanism forproducing a permanent decrease in the pitch angle and a rmanent increasein the mean diameter of t e helically wound layer; the said mechanismcomprising two elements with which the shafting is successively enga d,and by which its movement is contro led together with meansfor varyingthe relative angular position of these two elements with respect to eachother about the axis of the shafting as the latter is progressed.

4. A machine for the production of continuous lengths of flexibleshafting which comprises a winding head rotatable about the axis of theshafting, a pay-oil reel for delivering a core to the winding head, apullout mechanism for progressing the core and the helical layer woundupon it at a predetermined rate of speed and which controls the positionof the shafting at its points of engagement, a take-u reel operableindependently of the puli out mechanism, and means for rotatin saidpull-out mechanism around the axis of the shafting without like rotationof the take-up reel whereby said shafting is recoiled between the pointwhere it leaves the pull-out mechanism and the point where it is engagedby the take-up mechanism, the internal diameter of said helical layerbeing thereby enlarged and its pressure contact with the underlying corerelieved.

5. A machine for the production of continuous lengths of flexibleshaftin which comprises a winding head rotatable a ut the axisoftheshafting, a pay-ofi reel for deliveringa core to the winding head,a holding mechanism for progressing the core and the helical layer woundupon it ata predetermined rate of speed and for preventing the axialrotation o the shafting at its point of engagement therewith, 'a take-upreel operable independently of the holdin mechanism, and means forrotating sai take-up reel around the axis of the shafting without likerotation of the holding mechanism whereby said shafting is recoiledbetween the point where it leaves the holding mechanism and the pointwhere it is engaged by the take-up reel, the inner diameter of saidhelical layer being thereby enlarged and its pressure contact with theunderlying core re-- lieved.

6. A machine for the production of continuous lengths of flexibleshaftin which comprises a winding head rotatable a out the axis of theshafting, a pay-oil reel for delivering a core to the winding head, arecoil drum, a take-up mechanism for drawing the shafting from therecoil drum at a predetermined rate of speed,'and means for rotating therecoil drum around the axis of the shafting without like rotation of thetake-up mechanism whereby said shafting is recoiled between the pointwhere it leaves the drum and the point where it is engaged by the ulloutmechanism, the inner diameter 0 the helical layer being thereby enlargedand its pressure contact with the underlying core relieved.

7. In a machine for the manufacture of flexible shafting which comprisesa core and a helical layer of wire wound thereon, the combination of arotatable winding head, a take-up reel, and means engaging with thesurface of the said helical layer between the winding head and thetake-up reel, to prevent axial rotation of the said layer at the saidpoint of engagement, and means for retating the take-up reel at avariable predetermined speed in the same direction as that in which thewinding head revolves, and thereb effecting a controllable recoil of theshaft tween the said holding means and the said take-up reel.

8. machine for continuously fabricating flexible shafts havin a core anda superimposed helical layer w ich includes a core dispensing mechanism,windin mechanism, an take-up mechanism,the sai core disp nsing mechanismand windin mechanis being each mounted for rotation at independentlyadjustable speeds upon the axis of the fabricated product.

9. A machine for continuously fabricating flexible shafts havin a coreand a. superimposed helical layer w ich includes a core di nsingmechanism, winding mechanism, aniitake-up mechanism, the dispensingmechanism and winding mechanism being each mounted for independentrotation upon the axis of the product, and a rotatable drum positionedbetween the windin mechanism and the take-up mechanism an adapted toexert both an axial draft and transverse pressure on the helical layersof the shaft whereby the coils are held against relative movement on thesaid drum.

10. A machine of the class described, comprising a plurality ofcooperative units including means arran d to pay out a core wire, meansarran .to wind wires about said core wire, an means arranged to progressthe fabricated product longitudinally, all being mounted for relativerotation about the axis of said core wire, and cooperative to wind saidwires together and to so recoil the fabricated product as to relieve theinherent tension.

11. A machine of the class described, comprising a plurality ofcooperative units including means arran d to pay out a core wire, meansarran to wind wires about said core wire, an means arranged to progressthe fabricated product longitudinally, all being mounted for relativerotation about the axis of said core wire, and cooperative to wind saidwires together and to so recoil the fabricated product as to relieve theinherent tension, and means arranged to take up the fabricated productthus recoiled.

12. A machine of the class described, comprising a. plurality ofcooperative rotary units including core-dispensing mechanism, and wirewinding mechanism, cooperative to form a fabricated shaft, take-upmechanism, \nd means disposed between the winding mechanism and take-upmechanism arranged to rotate the fabricated shaft upon its axis oflongitudinal movement at a speed differing from the speed of rotation ofsaid core dispensing mechanism.

13. In a machine of the class described, the combination with meansarranged to dispense a core, of means arranged to form helicalconvolutions about said core, means for progressing the productlongitudinally and contemporaneousl rotating said product about the axisof its core, and a take-up for the product thus formed, cooperative withsaid progressing means, to untwist said fabricated product.

14. Mechanism arranged to wind together a plurality of wires into afabricated flexible shaft, and comprising wire-winding means, take-upmeans rotatable about the longitudinal axis of said shaft, and meansarranged to prevent the rotation of said shaft between said take-upmeans and said winding means, and thereb cooperate with said take-umeans to e ect recoil or untwisting of sai shaft.

15. Mechanism arranged to wind together a plurality of wires into afabricated flexible shaft, and comprising wire-winding means, take-upmeans rotatable about the longitudinal axis of said shaft, andcomprising a take-up reel, and a recoil or untwisting drum having afixed axis of rotation, around which the said fabricated shaft passes toprevent the axial rotation of said shaft between said take-up means andsaid winding means, and thereby cooperating with said take-up means toeffect recoiling or untwisting of said shaft to relieve inherentstresses.

16. An improvement in the art of continuously fabricating flexibleshafting which consists in first winding a helical coil of wire in closecontact engagement with a core, and then permanently enlarging the innerdiameter of the said coil without substantiall altering its axial lengthwith respect to t c said core, to thereby relieve the pressure contactbetween the said parts of the fabricated shaft before it is subjected tothe torsional strains incident to use.

17. An improvement in the art of fabricating flexible shafting incontinuous lengths which comprises the windin of superimposed closelycoiled helices of wire on a central core, and enlarging the innerdiameter of each helix before the succeeding one is wound, to therebyrelieve the pressure engagement between each of the said helices and theunderlying body.

18. An improvement in the art of fabricating flexible shafting incontinuous lengths which comprises the windin of a plurality of closelycoiled superimpose helices of wire on a substantially straight centralcore, and the twisting of each helix, after it has been of a plurality Iwound and before the next helix is applied, in the direction opposite tothat in which it was wound to thereby recoil and enlarge the innerdiameter of said helix and relieve its pressure contact upon theunderlying body" 19. An improvement in the art of fabrica-t ing flexibleshafting in continuous lengths,v which consists in successively windingupon a corebut in opposite directions helicalty 1o coiled layers ofwires each in close contact engagement with an underlying layer, and;then permanently relieving the initial close engagement of the said coreand the said layers by anuntwisting operation which simul-N taneouslyalters the diameter of both the over: lying and underlying coils as apart of the fabrication process and before the shaftin'g is subjected tothe torsional strains incident tq use. I

20. An improvement in the art of fabricat ing flexible shaftingini'continuous lengths whichconsists in first winding a helical coil ofwire in close contact enga ement with a core body and subsequentlyecreasing the number of turns in the helicalcoil without altering thelength of shaft and spooling the v product as thus fabricated.

21. An improvement in the art of fabricating flexible shafting incontinuous lengths so which comprises the formation of a composite corewhose outer'surface consists of elically dis osed coils of metal,winding thereon anot er helical layer of ,wire in a direction opposed tothe surface coils of the 3%: core and thereafter rotating the shaftingthus formed in the direction opposed to that; in which the outermosthelical layer was" wound, to thereby concurrently and permanentlyincrease the inner diameter of the outermost-helix and decrease theouter diameter of the immediately underlying helix, prior to thesubjection of the shafting to the torsional strains incident to use.

In testimony whereof I have hereunto 4c signed my name at Philadelphia,Pennsylvania, this 20th day of January, 1930.

ROBERT C. ANGELL.

